How to use the cligj.projection_mercator_opt function in cligj

    @cligj.projection_mercator_opt
    def cmd(projection):
        click.echo("%s" % projection)

@projection_mercator_opt
@click.option(
    '--dst-crs', default='', metavar="EPSG:NNNN", callback=to_lower,
    help="Output in specified coordinates.")
@options.sequence_opt
@use_rs_opt
@geojson_type_collection_opt(True)
@geojson_type_feature_opt(False)
@geojson_type_bbox_opt(False)
@click.pass_context
def bounds(ctx, input, precision, indent, compact, projection, dst_crs,
           sequence, use_rs, geojson_type):
    """Write bounding boxes to stdout as GeoJSON for use with, e.g.,
    geojsonio

      $ rio bounds *.tif | geojsonio

@projection_mercator_opt
@click.option(
    '--dst-crs', default='', metavar="EPSG:NNNN", callback=to_lower,
    help="Output in specified coordinates.")
@sequence_opt
@use_rs_opt
@geojson_type_collection_opt(True)
@geojson_type_feature_opt(False)
@geojson_type_bbox_opt(False)
@click.pass_context
def bounds(ctx, input, precision, indent, compact, projection, dst_crs,
           sequence, use_rs, geojson_type):
    """Write bounding boxes to stdout as GeoJSON for use with, e.g.,
    geojsonio

      $ rio bounds *.tif | geojsonio

@projection_mercator_opt
@sequence_opt
@use_rs_opt
@geojson_type_collection_opt(True)
@geojson_type_feature_opt(False)
@geojson_type_bbox_opt(False)
@click.pass_context
def bounds(ctx, input, precision, indent, compact, projection, sequence,
        use_rs, geojson_type):
    """Write bounding boxes to stdout as GeoJSON for use with, e.g.,
    geojsonio

      $ rio bounds *.tif | geojsonio

    """
    import rasterio.warp
    verbosity = (ctx.obj and ctx.obj.get('verbosity')) or 1